Solar Poloidal Magnetic Field Generation Rate from Observations and Mean-Field Dynamos

• Published in: Solar physics Vol. 299; no. 8; p. 111
• Main Author: Pipin, Valery
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01-08-2024; Springer Nature B.V
• Subjects: Astrophysics and Astroparticles; Atmospheric Sciences; Diffusion coefficient; Diffusion rate; Dynamo theory; Eddy diffusion; Evolution; Fluctuations; Magnetic fields; Magnetic flux; Meridional circulation; Photosphere; Photospheric observations; Physics; Physics and Astronomy; Rotating generators; Solar cycle; Solar magnetic field; Space Exploration and Astronautics; Space Sciences (including Extraterrestrial Physics; Turbulent diffusion; Vector potentials; Solar cycle; Dynamo; Magnetic fields
• ISSN: 0038-0938; 1573-093X
• DOI: 10.1007/s11207-024-02357-0

To estimate the hemispheric flux generation rate of the large-scale radial magnetic field in Solar Cycles 23 and 24, we use the photospheric observations of the solar magnetic fields and results of the mean-field dynamo models. Results of the dynamo model show the strong impact of the radial turbulent diffusion on the surface evolution of the large-scale poloidal magnetic field and on the hemispheric magnetic flux generation rate. To process the observational data set, we employ the parameters of the meridional circulation and turbulent diffusion from the Surface Flux-Transport (SFT) models. We find that the observed evolution of the axisymmetric vector potential contains the time–latitude patterns which can result from the effect of turbulent diffusion of the large-scale poloidal magnetic field in the radial direction. We think that the SFT models can reconcile the observed rate of hemispheric magnetic flux generation by considering radial turbulent diffusion and lower values of the diffusion coefficient.